From: Linus Torvalds Date: Tue, 13 Nov 2007 16:07:31 +0000 (-0800) Subject: Revert "ext2/ext3/ext4: add block bitmap validation" X-Git-Tag: v2.6.24-rc3~148 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0b832a4b93932103d73c0c3f35ef1153e288327b;p=pandora-kernel.git Revert "ext2/ext3/ext4: add block bitmap validation" This reverts commit 7c9e69faa28027913ee059c285a5ea8382e24b5d, fixing up conflicts in fs/ext4/balloc.c manually. The cost of doing the bitmap validation on each lookup - even when the bitmap is cached - is absolutely prohibitive. We could, and probably should, do it only when adding the bitmap to the buffer cache. However, right now we are better off just reverting it. Peter Zijlstra measured the cost of this extra validation as a 85% decrease in cached iozone, and while I had a patch that took it down to just 17% by not being _quite_ so stupid in the validation, it was still a big slowdown that could have been avoided by just doing it right. Cc: Peter Zijlstra Cc: Andrew Morton Cc: Aneesh Kumar Cc: Andreas Dilger Cc: Mingming Cao Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed